<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>阶乘和</title>
</head>
<body>
    <script>
        function jc(n) {
            var total = 1;
            for (var i = 1 ; i <= n ; i++) {
                total*=i
            }
            return total;
        } 
        
        function all(n) {
            var sum = 0;
            for (var i = 1 ; i <= n ; i++) {
                sum+=jc(i)
            }
            return sum;
        }
        console.log(all(4))
    </script>
</body>
</html>